 BEGIN         { FS="\n"; RS="" } 
               { Comment = 0    }
 /^[^ \t]/     { Comment = 1    }
 /^[ \t][ \t]/ { Comment = 1    }
 Comment       { gsub(/\n/,"\n# ")
                 $0 = "# " $0 
               }
               { print $0 "\n" }
